Frederick deacon marshall



March 5,1929. F. D. MARSHALL 1,704,093

APPARATUS FOR PRODUCING COKE AND GAS FROM SOLID CARBONACEOUS MATERIALOriginal Filed April 10, 1926 5 Sheets-Sheet March 5, 1929.

F. D. MARSHALL ,093

APPARATUS FOR PRODUCING COKE AND GAS FROM SOLID CARBONACEOUS MATERIALOriginal Filed April 10, 1926 3 Sheets-Sheet p i; /0 /0a /a f /w&

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ATTORN EY March 5, 19 .9- F. D. MARSHALL. 1,704,093

APPARATUS FOR PRODUCING COKE AND GAS FROM SOLID CARBONACEOUS MATERIALOriginal Filed April 10, 1926 s Sheets-Sheet INVENTOR ATTORNEY Patent edMar. 5, 1929.

ater I UNITED stars-s mm? c erics.

FREDERICK BEACON MARSHALL, 'OF WEYBRIDGE, ENGLAND.

, nrPAsAr s roa rnonncme COKE AND GAS rnorrsoLrD cannormcnous MATERIAL.

Application filed April 10, 1926, Serial No. 101,072, and in GreatBritain June 5, 1925. Renewed December This invention relates to'apparatus for simultaneous I manufacture of carbonaceous I gas and coke.The main object of this invention is the production of carbonaceous gasfrom material which also produces coke, as the result of thedistillation and carbonization of the material with which the apparatusis charged. Y

In the accompanying drawings illustrating the principle ofthis inventionin the best mode now known to me of applying that principle,

Fig. 1 is a vertical, central section of the retort structure at line1-1 of Fig. 3 showing a pair of top feed screws in elevation andillustrating by arrows the direction of fuel under carloonization and byother arrows the upward ascent of gas. The view also shows coke in theprocess of discharge from the under end of the retort; 5

Fig. Q-is'a transverse section 'of'the upper feeding casing structure atline22 of Fig. 1 and .showsthe feed casing with a charge of carbonaceousmaterial, such as bituminous coal. within the casing.

Fig. 3 is a transverse section through the retortcasing-proper and showsthe relations of the cells for containing material to be cari bonized,to the gas tubes or ducts.

Figs. 4 and 5 illustrate another form of the invention, Fig. ibeing averticalcentral section of-the retort structure at line 44: of Fig. 7and ,Fig. 5 being a vertical central section at line 5 ,5 of Fig. 4. j i

Fig. 6 is a transverse section of feed casing and with charge inp'lace,at line 66 of Fig. 4; and

Fig. 7'is'atransverse section of the retort at line 7,7 of Fig. 4. aFig. 8 illustrates another form ofcellular retort casing properconstruction and wherein' material to be carbonized is shown in ductsareshown.

Fig. 9 is a crosssection at line 9-9 of Fig.

1 and shows the location of the gas outlets at the upper end portions ofthe gas tubes...

Fig. 10' is a vertical, central section .ofthe place in vertical cellsand wherein also gas I shaft supporting glan'd'structure with a feedscrew shaft partially shown. Fig. 111s'a crossssection of what is shown.

in Fig. 10 at line 11'11 of Fig.10. in

Figs.. 12,. .13. and 14 are viewsof a screw shaft reduclng gear.

the upper I In the accompanying drawings, 1 is the retort casing properwherein the material to be gasified and coked is contained. 2 is thehead casing; 2" are a pair of noncontac ting feed screws which mayeither overlap or receive the peripheries of the helices just clearingeach other; 3 are the gas ducts-shown as connected by cross webs 00 tothe inner sides of the retort casing. It will be noted that these ductshave gas escape openings at their upper end portions. Their tops areclosed, but they are open at their under ends. The charge receivingcells 3' are open both at top and bot.- tom. The cell walls areindicated by 3*. All the duct or passageway walls are connected by websa. The retort casing 1 is enclosed by a spaced apart combustion orheating chamber wall 3 I To preventcoal or other material passing downthe gas ducts, the open topof each is fitted with a cover or stopper Sabove the gas duct escape slots 5.

4 is the expansion joint shownin this 13215;

at the bottom end of the retort casin and is filledwith a suitablepacking 4 5 is the coke receptacle which formsthe framework of balancedflap doors 6 shown attached to a rocker shaft 6 the ends of which arepro? vided with counter weights 7 for closing and maintaining the doorsin a closed position. 8 are the twin screw shafts;'9 is the gas outlet10 is theinlet for material under course of treatment; 11 are gas-tightsupporting glands from which the screws depend.

121is the turning gear which has been specially designed for the presentpurpose and which is connectible with an electric m0- torM by which amotorspeed of 1000 revolutions per minute is reduced by means. of thearrangement to give the feed screws a roscrew propellers aresituated inthe separate head casing .or upper section Q'which is attached to theupper end of the retort casing proper or lower section 1 which lattercasing may be heated if desired by the described method of my copendingapplication Ser. No. 101,07iiled April 10, 126, for the pur pose ofcarbonizing, gasitying and coking the material passing through theretort. The casing 2 containing the screws is situated outside the zoneof heat. The short screws in the upper, non-heated casing 2 act ascollectors of the material and propellers ot the same to force thematerial which is fed by these screws or propellers downwards intothrough vertical ducts of the heated body of the retortcasing or lowersection 1, where the material undergoes carbonization or gasilication.Said lower section 1 is the heatable, coal distillation structure of theapparatus.

The experience has been gained by the in 'ventor to effect lowtemperature carbonization at a temperature ranging between 900 1200 Fah.that, the thickness of the material under the process of carbonizationor gasification must not exceed tour and one-halt inches and thatprovision must be made for applying this heat to all tour sides of thematerial. As the density of the resultant coke from the material-isentirely due not to temperature but to the expansion of the materialwliile'in a semi-carbonized or semi-plastic condition and as thisexpansion exerts a great force,

provision must be madethat the walls of the duct-s through which thematerial is forced by the pressure, and also the screws are ofsufficientstrength to withstand the great pressure.

The bore of theupper, headcasing 2 and of the lower carbonizing sectionis practically the 'saine, and when both are seen empty they willrepresent a true bore from end to end of both sections when fittedtogether.

inches in cross-sectional dimension.

inch per hour and practically and commercially considered, it is highlydesirable that the cross-section ot the ducts shouldnot be over aboutfour and one-halt inchesalong the intermediate portions of theducts,where the active distillation of the coal takes place, adjacent andabove the lower portions of the ducts where the coking progressivelyeffected. p

These radial and transverse webs are an integral part of the retortcasing itself, being cast as part of the same; and by reason of theconductivity of cast iron and by molecular ailinity ot' the iron, theheat applied to the exterior of the retort is conducted through all thetranverse and radially disposed members and is so imparted to thematerial which fills the retort cells or ducts during its-passagethrough the same.

The said cells or ducts need not necessarily be of the samecross-sectional area or shape as they may be so shaped as to produceslabs of coke, bearingalways in inindthe four and one-half inchescondition or they may be disposed (Fig. 8) inhoneycomb form for thepurpose otproducing a briquette like form-0t v The said members or wallst'orinin g the cells or ducts are located between the outer casing andinner hollow gas ducts tor aiding the rapid withdrawal of the evolvedgases from the retort, and have nothing to do with the heating of thesame.

During the evolution of the gases, the gas outlet is under the influenceot minus atmospheric pressure owing to the action of the gas exhauster,not shown, but diagrammatically indicated. v v v l The evolved gasesfind their way to their outlet through the centres of the char es ofmaterial as, owingto the pressure exerted on all sides by the expansionof the charges during carboni'zation, very little or no gas can find itsway up between the outer sides of the charges and the inner surfaces ofthe containing cells or ducts. V

The coal and gas ducts being open at each end are naturallysusceptibleto the eX'hauster suction on the interior of the retort generally, andas the evolved gases seek toleave, the centres of the charges by thepath otl ei ing the leastresistance, it open for these gases to leavepartly direct through the upper portion of the charges'or partly throughthe lower ends of the gasducts, andthe arrows in the drawii'ig show theapproximate paths the gases take. The coal or distillation ducts areopen at their upper and under ends. The gas-ducts are open at their un=der ends, and though closed at their upper end openings by members Sinorder to prevent the coal vfrom being TEOl'CGtl down into them and socloggii'ig theducts, are provided at their upper end portionsadjacentthe members S with gas escape portssf Much value is attached to theseducts "as the easier and with less resistance the gasescan escape, thechances of their being cracked or split up is greatly lessened.

To increase the throughputcapacity'of the retort, the divisions or websin the: retort may be disposed in an annular manner and, provided alldivisions "are connected physi cally with the. inner wall of the retort,the

carboniza'tion of the interior columns of ma destructive consequences.

eject the charge of carbonized coke from the casing automaticallyandcontinuously before the pressure on the material leads to Accordingto the present form of my invention, this is efi'ected by theinstallation, atthe lower end oi the lower casing or sec- .tion 1 of acoke boxor receptacle within which a pair ot-flap doors d are installedworking on hinges; and which, when. in a horizontal condition, close thebottom of the superimposed casing in a practically gas.

tight manner as the edges of the flaps are bevelled to the same angle asthe. tapering sides of the coke box or receptacle against .which theycontact, so that the foot oft-he columns of coke in the casin rest onthe flaps which are kept in position by a lever attached to each flapwhich levers are controlledby weights or springs. l

The desired pressure tobe exerted by the;

' 'co-acting serewson the charge of material,

totorce-the same throu hthelower casin having been ascertained, thelevers are weighted accordingly so that when the pressure on the chargereaches a certain point the flaps are forced open and a portion of thechargein the form of coke is ejected into the gas-tight box orreceptacle below the. flaps. When the pressure is relieved, the weighton the levers causes the flaps to return to a horizontal position. Y

At intervals the coke receptacle isopenec and the coke removed duringwhich period therevoliition of the co-acting screws may be stopped and the fiapsheld up to 'cnsure against the enteringfof air into the retortcasing. v

The-design of the flap doors 6. may be varied and instead of hinging t1cm on their long sides they may be. hinged on their short sidesineither case being controlled by the outside levers fitted-with eitherweights" or springs. The flap doors Gare merely one form of coke escapecontrol apparatus for also offering a resistance to the downward feedingpressure and; load of the coal in its inltlal condition, in its actived1st1llat1on and gas evolving condition,and in its progressive coking.inthe lower portion of cachdis tillation .duct.

The. density of. the coke can, be"varied' by the, amount of pressure 1t1s sub ectedto during its formation in the retorta'nd this controllablevariation ot pressure is another feature of-my invention. j I I p V Totake up the expansion of the retort in a vertically, longitudinaldirection, it pro? outwardly ot-the receiver.

7 11 is applied. The casing has a bottom that is solid except for acentral shaft opening through which a shaft 8 extends upwardly throughthe fixed cover plate 13 of easing 2, and upwardly through the fixedcover it of casing 11 for reception of members of the turning gear 12. IWithin the gland'casing, there is'at its bottom portion a pair ofdiscshaped ball races 15 between which anti-triction balls 16 arelocated, the shaft passing through the races and upwardly through apiston 17 provided with piston rings 18. The piston is pinned to theshaft by pins 19 and has a length less than the distance between theupper race 18 and the gland casing cover, leaving a clear space 20 intowhich the piston may ascend on elongation of the shaft due to heat. Eachscrew is suspended from its piston which normally rests on the upperrace. Thebottom of the gland casing is provided with a packing '3 aroundthe screw shaft and the gland as a whole is gas-tight and constitutes agas-tight, anti-friction screw suspending mechanism that permits endwisemovement of the suspended screw. 7 The turning gear or driving mechanismwhich .is fixed on the upper casing cover, although it may be otherwisesupported, includes an addition to the gear 12 which is a spur gear, oneon the upper end oteach screw shaft, an intermediate spur gear 21 inmesh with gears 12. Norm gear 22 is mounted on the upper end portion ofa vertical stub shaft 23 and efl'ects rotation of the screw shaftssimultaneously in the same direction. Vorm gear 22 is in mesh with worm25 on a horizontal shaft 26 which is provided with a worm gear 27. 1This worm gear 27 is in mesh with an intermediate worm 28 on a shaft 2also of about 1000 revolutions per minute to a screw rotational speed offrom six to ten revolutions per hour, as above stated.

The stoppers S at the upper ends of the tubes'are fixed in place, thuspreventing entrance of the material into tne gas tubes or passageways;but the gas exits ports 8 are con tinuously open so that the. generatedgas may continuously escape therethrough, into the communicating space Sand then to the exit 9, while the retorting operation is active.

The rocker shaft 6 mounted in openings of the wall ot the receiver '5for cokeor other reid'ue ofdintillation, extends at both ends Each endhas a dependent arm 6* for reception of one or more removable weights 7,two of which are shown lit) s on each arm. The weights maybe increasedor diminished in number according to the character of the material to betreated. "Receiver 5 is practically air-tight and is provided with anopening 5 through which the residue of? distillation may be removed fromlime to time. Each opening is shown provided with a door 5.

The combustion chamber 3 is for heat applied during the rotor-tingoperation which may be a 'low temperature operation for which theapparatus is especially intended.

The intake is provided, in practice, with a gas-tight charging device 1Oany desired constructitui, the charging device is herein indicateddiagraniniatically.

In operation, succeeding initial charging, charge arresting andcarbonization, the feed screws may be driven continuously and the chargearresting doors may be continuously opened for either partial momentaryinterruption in escape, or, forcontinuous escape, of the coke into thecoke box. with the box door closed to prevent inrush of air, all de-Evolution and removal of the gas is con-' tinuous. The cl'iargingoperation maybe continuous or intermittent depending on the type ofcharging apparatus used. The dis harge of the coke into the coke boxisautomatically intermittent.

in Fig.5. 5, the as escape 9 is shown dischar 7 5 into adiagrammatically illustrated exhauster 9. The cxhauster connection issu'tlicient in practice to ell ect the ascentof gas into the escape9,'notwithstanding the pressure on the charge between the feed screws rand flap doors. .SOEHQ of the ascending gas and for forcing the escapesfrom fissures in the col-1e and some of it from material M there-above;

The coal ducts ret'crred to may be properly designated distillationducts. The under helices or the feed scre vs are effective to force andbreak up said material against the upper ends 01 the uistillation ductwalls n'iaterial downwardly into and through the ducts. .Vhen the coal-:l.ucts are filled andthe feed screws are in action, the coal or othermaterial. is forced into the upper, open ends of the coal ducts. and isunder 5-;UTQ- l()\\11W2l]JtllY to the echo 4 control apparatus. d hilethis A crmits, by vibration of the tree yes oi the flap doors on whichtie coke initially rests, continuous escape of the coke according toadjustments of the weights 7, the apparatus, nevertheless, otters such aresistance to the downward pressure that the pressure densities the cokesubstantially andfirmcoke is produced. It will be observed that theheatable, metal wallsot the coal and gas ducts are integral and serve toconductcxteriorly applied heat-to and through the material in the coalducts; and that there is a plurality of coal ducts subjacent the underend of each feed screw. The integrally and metallically walled, coalducts are raised to a temperature sufficient to render portions of thecoal, as it is forced compressively downward from the upper end portionof the coal ducts, plastic; and in this condition gas is freely evolved,the plastic condition permitting the feed screw pressures to condenseand solidity I the coke formed in the lower portion of the coal ductsagainst the flap doors or gates carried by the adjustable, weightedrocker shafts 6 When the apparatus is in operation these flap doors orgates are never closed,'butare constantly vibrating and thus permitcontinuous discharge of the solidified or densilicd coke which, withallthe superincumbentmaterial in the coal ducts, is under continuousdownward pressure by the feed screws. .The

teed screws and their operating mechanism constitute, in effect, acontinuously operable means-tor feeding and also t'orcing'the coal orother gasifiable and coke producing material into and through thedistillation ducts and compressing thecoke into an extremely firm, densecoke against the resistance offered by the coke control discharge meansoperable to form a resistance to the compressive densi fication of thecoking, plastic material thereabove. The feed screws are spiral screwsof the same hand and are shown of the same pitch. The cross section ofeach screw is that of a spiral screw. The screw helix of reach screwextends from an intermediate keeping the in-t'ed coal and the cokingplastic stratum or strata under constant pressure as described, theformation of thin and fragile walled coke cells is prevented and a densecompact coke product obtained. Such a densitication is of very greatimportance to the coke product as it does not break up or give oii' cokedust as is the case with coarsely' cellular coke, Moreover,theconsta'ntcompression is favorable to evolution of the evolving fromthe coking portion of the'coal and from the coal.

WhatI claim is i 1. In apparatus for simultaneous production of gas andcoke from carbonaceous material, the combination of an upright casinghaving an upper and a lower section; said upper section being providedwith a preliminary coal charging apparatus, and means to effect escapeoi ascending gas .or gaseous vapor, and being open at its under end fordis charge of the material under feed screw pressure; and, apluralityotadjacent vertical, downwardly feeding, spiral feed screws of the samehand within said upper section of the casing; said lower section of thecasing being of metal and being provided with a plurality of vertical,metal distillation duct walls having their upper ends opposed to andspaced apart from the under end of each of said feed screws, each feedscrew having a cross section dimensioned to cover a plurality of theupper ends of the ducts, and the distillation ducts being open at theirlower ends above the bottom wall of the lower section of the casing, forescape of gas and coke; mechanism for removing the coke;

- mechanism for rotating said feed screws; a

combustion chamber around the distillation duct wallspeach of said feedscrews being efiective to force said material into the upper endsthereof and for forcing the material downwardly into and through theducts; the duct walls conducting heat received by them to thecarbonaceous material in the ducts; and gas oil -take ducts extendingupwardly from the lower portion of the under section.

2. In apparatus ofthe class described, the combination of a plurality ofupright, continuously revoluble, spiral feed screws of the same handmounted within a casing and arranged to deliver and to force materialcontinuously downwardly into the upper open ends of a series ofintegrally and metal walled elongated, upright ducts of small crosssection relatively to that of the casing above the ducts, and throughand out of said ducts; each feed screw being dimensioned to cover aplurality of the upper ends of the ducts; and upright metal structureprovided with said ducts, means for eXteriorly heating said metalstructure to render plastic therein descending portions of the materialfor evolution of gas and production of coke in lower portions of saidducts; and continuously operable, coke discharge controlmechanism'efiective to ofier resistance to the pressure produced by thedownward feed of the material; and means for conducting the generatedgas upwardly and out of the apparatus; said feed screws having theirunder ends adjacent, but spaced apart from, the upper open ends of saidducts; and said integrally and metal walled ducts being arranged inparallel. groups wherein each group comprises a plurality of ductssubjaoent the under end of each :teed screw.

3. In coal gas and compressed coke making apparatus, the combination ofa continuously operable, coal feeding mechanism, said mechanismincluding a casing and spiral teed screws mounted therein; a cokedischarge control mechanism; and, interposed between said feed screwsand said coke discharge control mechanism, an elongated, metaldistillation structure having a plurality of sets of 0pen-ended,lengthwise extending, distillation ducts grouped in each set around andenclosing a gas escape duct, the ducts in each set of distillation ductsbeing opposed to one of said feed screws, each feed screw beingdimensioned to cover the upper ends of a plurality of said ducts; thewalls of all the ducts being integral, and each feeding mechanism beingoperable not only to feed into adjacent open ends of said distillationducts, but also to force the material fed compressively into and to fillthe same, to compress therein formed coke against the resistance of thecoke discharge control mechanism when the same is in coke arrestingposition, and past the same when it is in position for discharge ofcoke; said coke escape control mechanism being operable to arrest andresist the escape of coke against the pressure of said coal feedingmechanisms and also permit the discharge of the coke; and means forexteriorly heating said structure; the ends of the gas escape ductsadjacent the coal feeding mechanisms being closed to prevent iii-feed ofcoal and adj acently provided with gas escape ports; and the ends ofsaid gas escape ducts adjacent the coke discharge control mechanismbeing open for intake of gas.

Signed at New York city, in the county oi New York and State of NewYork, this 12th day of March A. D. 1926.

FREDERICK DEACON MARSHALL.

